And despite that, the software’s focus is to cut the cord between your iOS device and your computer, so you can spend less time managing your digital content. With several interface improvements, new apps and new services, iOS 5’s goal is to get us in and out of our iDevices more quickly.

Of the many new items, iCloud, Notifications Center, Reminders and iMessage are the most noteworthy. They all work together to streamline the way you access and share data between multiple devices, like your computer and your iPhone, to make your digital life tidier and easier to manage.

But one thing in particular makes iOS 5 feel like Apple’s most ambitious mobile software update yet: iCloud. This is not Apple’s first try at an online storage and synchronization service. MobileMe, iCloud’s most recent predecessor, had a buggy launch that eventually resulted in an e-mail outage affecting thousands of customers. Critics dubbed the episode “MobileMess.”

In his keynote speech introducing iOS 5, Steve Jobs promised that iCloud would “just work” — but not without owning up to the embarrassing failure of MobileMe.

“You might ask, why should we believe them?” Jobs said. “These are the people who brought us MobileMe.”

The good news is that unlike MobileMe, iCloud does work fine with the key features in iOS 5, which suggests Apple may finally have a solid “cloud” solution on its hands.

Snip, snip

The iCloud service is integrated into some key aspects of iOS 5: photos, e-books, device backups, document storage and, of course, iTunes music.

I imagine that the most popular iCloud-powered feature among customers will be PhotoStream, an option you can toggle on to automatically synchronize photos across multiple devices. This was my favorite feature of iCloud. (Yes, Microsoft did this first with Windows Phone 7 and SkyDrive, and it worked about the same.)

On your iPhone, you toggle on PhotoStream and log in with your Apple ID, and then whenever you snap a picture, that same photo appears on your Mac or Windows PC through the PhotoStream channel. If you have an iPad running iOS 5, you can turn on PhotoStream and access your iPhone-taken photos there right away, too.

You no longer have to plug your iOS device into a computer with a USB cord (unless you really want to). Backups and synchronization can all happen on the device itself, as long as you’ve stored your data in iCloud.

It’s kind of like having a camera with a magic photo roll — you snap your photo once, and you can access it immediately on multiple devices. That spares you the trouble of having to import photos manually just to see them on another screen. This also works as an automatic backup system: It’s unlikely you’ll lose photos in the future, because they’ll be kept safe inside your PhotoStream.

My main complaint is that PhotoStream only kicks in when Wi-Fi is turned on, so if you’re outdoors without access to a router, you’ll have to wait till you get back home to transfer the photos over Wi-Fi to your PhotoStream. That’s a lame limitation, and I suspect the carriers have something to do with it.

The other most useful iCloud feature is over-the-air backups for the iPhone, iPad and iPod Touch. Just by switching on “iCloud Backup,” you can automatically back up device data over the internet.

Then if you lose your iPad, for example, and you take a brand-new one out of the box, you can log in to iCloud and tap “Restore from backup,” and you’ll have your apps, notes, calendar and everything back. I tested this on an iPad 2 running iOS 5, and it took only about 5 minutes to restore from a backup. It worked great. (Yes, this requires Wi-Fi, too.)

The big picture of iCloud’s over-the-air device backup and restoration is that the days of “Connect to iTunes” are over. You no longer have to plug your iOS device into a computer with a USB cord (unless you really want to). Backups and synchronization can all happen on the device itself, as long as you’ve stored your data in iCloud.

The other aspects of iCloud are a little less interesting, though certainly welcome. If you’re reading an e-book through iBooks on your iPhone, and you create a note, you can later pop open the same book on your iPad and see the same note.

Same goes for documents. Edit a Keynote presentation in the Keynote app on your iPhone, for example, and that edit will appear in Keynote app when you open the same presentation on your Mac. I was already doing this with Dropbox long before this feature’s debut, so it’s not very impressive to me, but it works fine.

iCloud also synchronizes your purchased content across devices. With iTunes music, if you buy a song through iTunes on your Mac, you can automatically download the same song onto your iPhone as well, without having to pay for it again. That’s convenient, but I wish we could just store all our music on iCloud and stream the songs wirelessly instead, rather than have to download the files locally.

Same goes for apps — apps purchased on one device in the App Store can be downloaded on another iOS device through iCloud.

iCloud is also integrated into the Apple calendar apps now, so when you create a calendar event, it shows up in the calendar app on your other Apple devices, too.

Overall, in its current state, iCloud is mostly beneficial for people who own an Apple family of products: a Mac and at least one iOS device. I doubt Windows users will get much out of iCloud, because the only easily usable feature available to them is PhotoStream.

And that’s really Apple’s goal: to reel you into its ecosystem with the convenience of iCloud. If you own an iPhone, now it makes more sense than ever to have a Mac and an iPad, versus a Windows PC and an Android tablet, just to take advantage of iCloud.

Notifications Center is designed to make iOS less of a naggy experience, by putting all your alerts in one quiet place.

The Notifications Center is the best new feature in iOS 5. Indeed, it looks a lot like Android’s notifications center, though with a little more polish. It’s designed to make iOS less of a naggy experience, by putting all your alerts in one quiet place.

The way iOS used to work was, if you were in the middle of something such as playing a game and you received a text message, an annoying blue box with the message popped up in the middle of the screen, stopping the action and interrupting you.

With the new Notifications Center, the message will instead appear in a less obtrusive strip at the top of the screen, and you can tap on it to reply to the message.

That’s how all notifications work now in iOS 5. If you get a new Facebook message, the alert appears in the Notifications Center. If someone Likes your photo on Instagram, that appears in your Notifications Center. You can look at all the notifications in a neat list if you just swipe your finger down from the top of the screen.

The other major new app is Reminders, which acts like a to-do list with an alarm system. You can create a reminder to call your wife at 3 p.m. when you leave work, and as you step out of the office, that reminder will pop up. Or you can just create a reminder to do something at a certain time, like sending an e-mail to your coworker tomorrow at 9 a.m. The reminders are displayed in a check list.

To be frank, I didn’t really get what the point of Reminders was until Apple showed off the iPhone 4S with Siri. It’s insanely easy to create a reminder just by talking to Siri: “Remind me to write review on iOS 5 on Monday,” for example. Therefore, I believe that iPhone 4S customers will really enjoy Reminders the most. Everyone else though will probably view it as a ho-hum to-do list.

I generally don’t like that Reminders is basically a separate events organizer from Calendar. The two apps do not work together, so you have to launch Reminders just to look at your to-do list for the day, and then launch Calendar to look at your meetings for the day. I’d prefer if Reminders were integrated into the Calendar app to get an all-in-one view of what I have to do all month.

iPhone customers are going to love iMessage, and carriers are going to hate it.

Another nifty addition is iMessage. Now you can set your text-messages to send from your iTunes ID e-mail address instead of your phone number. So when you send a text to another friend with iMessage turned on, it shows up as a blue chat bubble, and it doesn’t count as a text message in your cellphone plan. If you send a text to someone who doesn’t have an iPhone or iMessage, the chat bubble is green, meaning it counts as an SMS from your cellular plan.

iPhone customers are going to love iMessage, and carriers are going to hate it.

What else is new? Subtle differences, mainly.

The iPad’s Safari browser now has tabs to easily switch between different webpages, just like most desktop browsers do today.

There’s also a new option to split the iPad keyboard in half and lift it to the middle of the screen, so you can type with your thumbs. I still prefer typing in landscape mode with all my fingers, but I think people who have to stand while typing on the iPad, such as doctors, will use this feature most.

On the iPhone, you can now launch the camera from the lock screen, as opposed to having to unlock the phone and open the Camera app. To get to the shortcut, you just press the Home button twice, and a small camera icon appears in the bottom-right corner. You can also snap the photo using the Volume button.

Additionally, the Photos album app now includes editing tools for quick touch-ups like red-eye removal, to spare you the need to launch a separate app just to apply minor edits. These are tiny improvements to make taking pictures a faster experience.

Stable, painless, and free

Upgrading from iOS 4 to iOS 5 was a smooth experience for me, and I didn’t notice any major bugs. The biggest reason everyone should download this software update is iCloud. Just start setting up your iOS device(s) and Mac to use iCloud, and at some point you’ll never have to manually sync with iTunes again.

The second biggest reason you should get this software update is that it’s free. I mean, what’s stopping you? Plus, the Notifications Center and iMessage are must-haves.

The new iOS 5 software and iCloud are impressive version-one products. However, only time will tell whether Apple’s new online service remains stable when millions of customers plug in to iCloud in the coming weeks. That will be the next big test.